Particulates may be used as filler additives to polymer compositions such as thermoplastic polymer compositions. Filled polymers are widely used in many fields of application. Adding fillers provides the advantage that the physical properties of the polymer material can be optimized, e.g. to increase the stiffness and toughness and to modify heat conductivity or heat deflection temperature (HDT) of the composite material. Additional benefits of filler-modified polymers are their versatility and an exceptional price/volume performance ratio. For example, the price of the polymer composite usually decreases with increasing filler content.
Filler comprising polymer materials are used in various fields such as automotive, furniture, electrical appliances and other fields.
However, small particles such as fillers tend to form aggregates, which deteriorate the properties of the polymer composite material. In some resins, at a specific bulk density, the aggregation tendency of fillers and in particular spherical fillers generally becomes significant and problematic. At the same time their aggregation tendency makes handling and confectioning of fillers difficult. For example, pneumatic conveying of fillers may be inefficient.
Thus, there is a need for improved filler materials which exhibit reduced aggregation tendency and improved dispersion qualities. The same problems and needs apply to pigments for polymers. The handling and dispersion of such pigments, e.g. inorganic or organic pigments in plastics frequently still presents difficulties. In particular it is desirable to provide improved pigments which do not compact during extrusion, have the same color tone as the non-modified pigments and which show little or no flocculation and no loss of gloss.